A cryptic pregnancy is when a person is unaware that they are pregnant until late in the pregnancy. This may occur as late as the third trimester or only when a person goes into labor.

In this article, we discuss what to know about cryptic pregnancies, including symptoms, risk factors, and when to see a doctor.

a woman sat in a cafe who is maybe unaware she is pregnant because she has a cryptic pregnancyShare on Pinterest
A person with a cryptic pregnancy may not realize they are pregnant until the third trimester.

People with a cryptic pregnancy are unaware that they are pregnant. They may only realize they are pregnant during the last few weeks of pregnancy or when they give birth.

Often, someone with a cryptic pregnancy does not experience typical symptoms of pregnancy, such as:

Learn more about the early signs of pregnancy here.

In addition to not being aware of a pregnancy, some people may deny that they are pregnant.

Recent studies on cryptic pregnancy are hard to come by. However, those available studies have suggested that cryptic pregnancies occur more often than doctors might think.

A 2011 review found that different population studies found the rate of cryptic, or denied, pregnancy at 20 weeks to vary between 1 in 475 people to 1 in 516 people. Other studies referenced in the review found the rate of denied pregnancy that continues to labor is around 1 in 2,500 pregnancies.

Doctors classify most cryptic, or denied, pregnancies as affective, psychotic, and pervasive.

  • Affective: People with affective denial of pregnancy acknowledge they are pregnant but do not prepare emotionally or physically for pregnancy, childbirth, and parenting.
  • Psychotic: People with psychotic denial of pregnancy may have mental illnesses, such as schizophrenia or bipolar disorder. They may experience symptoms of pregnancy but may link them to delusional causes.
  • Pervasive: People with pervasive denial of pregnancy experience a lack of emotional significance to pregnancy and are unaware that they are pregnant. They may also become aware of pregnancy late and avoid seeking medical attention.

How long can a cryptic pregnancy last?

It can be difficult to know how long a cryptic pregnancy lasts. For example, if a person only realizes they are pregnant due to the onset of labor, it may not be possible to assess when the pregnancy started.

People with cryptic pregnancies may not experience any typical pregnancy symptoms or only vague ones. In some instances, people may only experience noticeable symptoms days before giving birth.

One 2020 case of cryptic pregnancy saw a person experience 3 days of lower back pain, abdominal discomfort, and constipation before going into labor. The late onset of severe symptoms may dissuade people from seeking medical consultation or testing for pregnancy.

There is no clear indicator of cryptic pregnancy.

Researchers previously thought that women with cryptic pregnancies typically had one or more of the following factors:

  • younger age
  • learning disabilities
  • poor social and family support
  • mental illnesses
  • history of drug use

However, researchers are yet to define clear causes of cryptic pregnancy.

Doctors have yet to establish risk factors for cryptic pregnancy because they are unable to identify common features.

However, a 2021 study assessed 71 people that experienced pregnancy denial against 71 control subjects. Researchers found that risk factors for pregnancy denial included:

  • younger age
  • being single
  • a history of psychiatric conditions

As the cryptic pregnancy progresses, doctors have a better chance of detecting pregnancy.

Since women with cryptic pregnancies may only become aware of pregnancy in the later terms of pregnancy, they may have unassisted deliveries because they have not prepared for birth.

If a person does not realize they are pregnant, they may also not receive adequate care or make necessary lifestyle adjustments to support pregnancy.

Older studies note that cryptic, or denied pregnancy, can increase the newborn risk of:

  • prematurity
  • small size
  • hospitalization
  • death

People with denied pregnancy may deliver unexpectedly, in some cases, giving birth without assistance.

Unassisted deliveries can be dangerous for both the pregnant person and their baby. According to the American College of Obstetricians and Gynecologists, there is around a twofold increase in the risk of perinatal death when giving birth at home. However, the rate still remains low, at around 1-2 in every 1,000 births.

People who are confident they are pregnant, despite having a negative pregnancy test, should speak with their doctor or another healthcare professional.

The most specific and accurate pregnancy test is a blood test. Doctors will check for the presence of human chorionic gonadotropin (HCG) in the blood. HCG is a hormone that the placenta releases.

If a person follows the directions of an at-home urine pregnancy test correctly, the results are typically reliable.

Other situations may cause a false-negative result. This means people are pregnant, but the test gave a negative result.

Factors that can cause a false-negative result include:

  • taking the test too early
  • using diluted urine for a pregnancy test
  • checking test results too soon

Certain medications can also affect the results of a pregnancy test, causing a false-positive result. This means the test shows positive for pregnancy when a woman is not pregnant.

Medications that affect pregnancy test results include:

  • promethazine
  • Parkinson’s disease drugs
  • antianxiety medications
  • antipsychotic medications
  • diuretics
  • anticonvulsants
  • fertility medications

Some brands of pregnancy tests are less reliable than others and their sensitivities may vary from test to test. The packaging of the at-home urine pregnancy test should indicate the test’s sensitivity.

If someone believes she is pregnant, but the urine test is negative, they should test her urine again in a few days. If the test is still negative, they should speak with a doctor and request a blood test.

Learn more about the factors that can cause a false negative pregnancy test here.

Anyone experiencing pregnancy symptoms should consult with a doctor to confirm the diagnosis or provide emergency care if necessary.

As people with a cryptic pregnancy may not realize they are pregnant until late, it is essential they seek prompt medical assistance when necessary.

The sooner a person confirms pregnancy and begins receiving appropriate care, the higher the chances of a successful pregnancy.

Several lifestyle factors such as diet, smoking, and alcohol use can all affect fetal health. If a person is not aware they are pregnant, then there may be a risk of them engaging in behaviors that can negatively affect their pregnancy.

In cryptic pregnancy, a person does not realize they are pregnant until a late trimester or even until they are in labor.

Being unaware of pregnancy may mean a person does not receive adequate care or make healthful lifestyle adjustments. Both of these factors can lead to complications in fetal development.